Worn shaft bushes allow air leaks. No repair kit exists – must be machined and bushed.
Mikuni BDS26 Service Manual: Complete Overhaul & Tuning Guide 1. Overview of the Mikuni BDS26
| Part Type | Recommended Kit / Part No. | Notes | | :--- | :--- | :--- | | | Genuine Mikuni MK-BDS26-16 | Contains gaskets, O-rings, float valve, and screws. Fits Yamaha Virago/V-Star 250. | | Aftermarket Kit | All Balls 26-1632 | High quality alternative that includes OEM-sized jets. Fits Yamaha SRV250. | | Main Jet | Mikuni N100-604 (Large Round) | Sizes available in 2.5 increments. | | Pilot Jet | Mikuni VM28-486 | The jet that controls the idle circuit. | mikuni bds26 service manual
Work in a well-ventilated area. Wear nitrile gloves and eye protection. Carburetor cleaner will ruin rubber seals and blind human eyes. Tools Needed:
Connect a vacuum gauge or manometer to the vacuum ports on the engine intake manifolds. Bring the engine up to standard operating temperature. Worn shaft bushes allow air leaks
Diaphragms can crack, and tiny passage ports clog easily. 2. Tools Required for Service
Remove the top cap to inspect the rubber diaphragm. Look for tears, cracks, or hardening. 5. Rebuilding and Reassembly Overview of the Mikuni BDS26 | Part Type
A responsible service manual includes a “What NOT to do” section:
2.0 to 2.5 turns out from lightly seated
Before beginning a service, it is crucial to understand the components of your specific carburetor set: Mikuni BDS26 Go to product viewer dialog for this item. (Dual Setup) Bore Size: 26mm Main Jet: Varies by model (e.g., #95, #100) Pilot Jet (Slow Jet): Typically #15 or #17.5 Needle Jet/Jet Needle: Controls mid-range fuel delivery